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Background Little is known about the specificity of Bartonella spp. immunofluorescent antibody (IFA) assays in dogs. Bacteremia in sick dogs most often has been associated with Bartonella henselae (Bh), Bartonella vinsonii subspecies berkhoffii (Bvb), and Bartonella koehlerae (Bk). Clarification of the diagnostic utility of IFA serology when testing against these organisms is needed. Objective To evaluate the specificity of Bartonella IFA assays utilizing 6 cell culture–grown antigen preparations. Animals Archived sera from SPF dogs (n = 29) and from dogs experimentally infected with Bvb (n = 10) and Bh (n = 3). Methods Antibodies (Abs) to Bvb genotypes I, II, and III, Bh serotype I, strains H-1 and SA2, and to Bk were determined by IFA testing. Results Serum from naive SPF dogs shown to be negative for Bartonella bacteremia did not react with any of the 6 Bartonella antigens by IFA testing. Dogs experimentally infected with Bvb genotype I developed Abs against homologous antigens, with no cross-reactivity to heterologous Bvb genotypes, Bh H-1, SA2 strains, or to Bk. Dogs experimentally infected with Bh serotype I developed Abs against Bh H-1, but not to Bh SA2 strain with no cross-reactive Abs to Bvb genotypes I–III or to Bk. Conclusions and Clinical Importance Bartonella spp. Ab responses during acute experimental infections are species and type specific.

After a short-term fever, complex regional pain syndrome, characterized by hyperalgesia, intermittent swelling, erythema and cyanosis of both feet, was diagnosed in a female veterinarian. The woman was infected with Bartonella koehlerae and she was also Bartonella vinsonii subsp. berkhoffii seroreactive. Having failed other treatments, symptoms resolved following initiation of antibiotics.

PCR amplification targeting the 16S rRNA gene was used to test individuals with and without extensive arthropod and animal contact for the possibility of hemotropic mycoplasma infection. The prevalence of hemotropic mycoplasma infection (4.7%) was significantly greater in previously reported cohorts of veterinarians, veterinary technicians, spouses of veterinary professionals, and others with extensive arthropod exposure and/or frequent animal contact than in a previously reported cohort of patients examined by a rheumatologist because of chronic joint pain or evidence of small-vessel disease (0.7%). Based upon DNA sequence analysis, a Mycoplasma ovis -like species was the most prevalent organism detected; however, infection with “ Candidatus Mycoplasma haematoparvum” and a potentially novel, but incompletely characterized, hemotropic Mycoplasma species was also documented. Historical exposure to animals and arthropod vectors that can harbor hemotropic Mycoplasma spp. should be considered during epidemiological investigations and in the evaluation of individual patients.

Patients with infection from bacteremic Bartonella spp., tested using Bartonella Alphaproteobacteria growth medium (BAPGM), were retrospectively categorized into one of two groups that included those whose blood was collected once (group 1; n = 55) or three times (group 2; n = 36) within a 1-week period. Overall, 19 patients (20.8%) were PCR positive for one or more Bartonella spp. using the BAPGM platform. Seven patients (12.7%) in group 1 tested positive, and 12 patients (33.3%) in group 2 tested positive. Detection was improved when the patients were tested three times within a 1-week period (odds ratio, 3.4 [95% confidence interval, 1.2 to 9.8]; P = 0.02). Obtaining three sequential blood samples during a 1-week period should be considered a diagnostic approach when bartonellosis is suspected.

Background Bartonella alpha-Proteobacteria growth medium (BAPGM) enrichment culture has proven useful for documenting Bartonella species infection and has facilitated growth of other fastidious bacteria from human samples. Purpose To report non-Bartonella bacterial isolates obtained from canine samples cultured using BAPGM enrichment culture. Animals Between 2004 and 2008, 695 specimens from 513 dogs were tested by the NCSU-IPRL using the BAPGM enrichment culture. Over the same period of time, blood samples from 270 dogs were cultured by the NCSU-CML using Bactec-Plus Aerobic/F media. Methods BAPGM isolates were characterized using Bartonella genus primers and 16S rDNA primers followed by DNA sequencing. NCSU medical records were retrospectively reviewed. Blood culture results from the NCSU-CML were compared with BAPGM blood culture results. Results Seventy-nine non-Bartonella isolates were obtained from 69/513 dogs. The most commonly isolated phylum was Proteobacteria (48.1%) with alpha-Proteobacteria being the most commonly isolated class. Staphylococcus and Sphingomonas were the most commonly isolated genera. The majority of the remaining isolates were bacteria that are rarely isolated from canine samples. Comparison of NCSU-CML and IPRL (BAPGM) blood culture isolates showed alpha-Proteobacteria were isolated more often from BAPGM. Conclusions and Clinical Importance Use of insect cell culture enrichment medium, such as BAPGM, appears to enhance the growth of alpha-Proteobacteria, but also results in isolation of non-alpha-Proteobacteria from sick dogs. Future studies are needed to elucidate the utility of BAPGM and other “nonconventional” growth media and methods for isolation of fastidious organisms and to determine if these organisms play a causal role in disease development.

Here, we report latent infections with Bartonella quintana and a hemotropic Mycoplasma sp. in a research colony of cynomolgus monkeys ( Macaca fascicularis ). Sequence alignments, evolutionary analysis, and signature nucleotide sequence motifs of the hemotropic Mycoplasma 16S rRNA and RNase P genes indicate the presence of a novel organism.

Serum and blood samples from 192 patients, who reported animal exposure (100.0%) and recent animal bites or scratches (88.0%), were screened for antibodies by indirect immunofluorescence assays and for bacteremia using the BAPGM (Bartonella alpha Proteobacteria growth medium) platform. Predominant symptoms included fatigue (79.2%), sleeplessness (64.1%), joint pain (64.1%), and muscle pain (63.0%). Bartonella spp. seroreactivity or bacteremia was documented in 49.5% (n = 95) and 23.9% (n = 46) of the patients, respectively; however, indirect immunofluorescence antibodies were not detected in 30.4% (n = 14) of bacteremic patients. Regarding components of the BAPGM platform, Bartonella DNA was amplified from 7.5% of blood (n = 21), 8.7% of serum (n = 25), and 10.3% of enrichment culture samples (n = 29). Polymerase chain reaction (PCR) on only extracted blood would not have detected Bartonella infection in 34.7% (16/46) of bacteremic patients. Serology, in conjunction with blood, serum, and BAPGM enrichment culture PCR, facilitates the diagnosis of Bartonella spp. bacteremia in immunocompetent patients.

Bartonella vinsonii subsp. berkhoffii , Bartonella henselae , or DNA of both organisms was amplified and sequenced from blood, enrichment blood cultures, or autopsy tissues from four family members. Historical and microbiological results support perinatal transmission of Bartonella species in this family. It is of clinical relevance that Bartonella spp. may adversely influence human reproductive performance.

After raccoons were trapped and removed from under a house in New York, the owner and her two Papillon dogs became infested with numerous rat mites (Ornithonyssus bacoti). Two weeks later, both dogs developed pruritus, progressively severe vesicular lesions, focal areas of skin exfoliation, swelling of the vulva or prepuce, abdominal pain, and behavioral changes. Two months after the mite infestation, the owner was hospitalized because of lethargy, fatigue, uncontrollable panic attacks, depression, headaches, chills, swollen neck lymph nodes, and vesicular lesions at the mite bite sites. Due to ongoing illness, 3 months after the mite infestation, alcohol-stored mites and blood and serum from both dogs and the owner were submitted for Bartonella serology and Bartonella alpha Proteobacteria growth medium (BAPGM) enrichment blood culture/PCR. Bartonella henselae DNA was amplified and sequenced from blood or culture specimens derived from both dogs, the owner, and pooled rat mites. Following repeated treatments with doxycycline, both dogs eventually became B. henselae seronegative and blood culture negative and clinical signs resolved. In contrast, the woman was never B. henselae seroreactive, but was again PCR positive for B. henselae 20 months after the mite infestation, despite prior treatment with doxycycline. Clinicians and vector biologists should consider the possibility that rat mites may play a role in Bartonella spp. transmission.

Background: Hemotropic mycoplasmas are epicellular erythrocytic bacteria that can cause infectious anemia in some mammalian species. Worldwide, hemotropic mycoplasmas are emerging or re-emerging zoonotic pathogens potentially causing serious and significant health problems in wildlife. The objective of this study was to determine the molecular prevalence of hemotropic Mycoplasma species in little brown bats (Myotis lucifugus) with and without Pseudogymnoascus (Geomyces) destrucans, the causative agent of white nose syndrome (WNS) that causes significant mortality events in bats. Methods: In order to establish the prevalence of hemotropic Mycoplasma species in a population of 68 little brown bats (Myotis lucifugus) with (n = 53) and without (n = 15) white-nose syndrome (WNS), PCR was performed targeting the 16S rRNA gene. Results: The overall prevalence of hemotropic Mycoplasmas in bats was 47%, with similar (p = 0.5725) prevalence between bats with WNS (49%) and without WNS (40%). 16S rDNA sequence analysis (~1,200 bp) supports the presence of a novel hemotropic Mycoplasma species with 91.75% sequence homology with Mycoplasma haemomuris. No differences were found in gene sequences generated from WNS and non-WNS animals. Conclusions: Gene sequences generated from WNS and non-WNS animals suggest that little brown bats could serve as a natural reservoir for this potentially novel Mycoplasma species. Currently, there is minimal information about the prevalence, host-specificity, or the route of transmission of hemotropic Mycoplasma spp. among bats. Finally, the potential role of hemotropic Mycoplasma spp. as co-factors in the development of disease manifestations in bats, including WNS in Myotis lucifugus, remains to be elucidated.

To the Editor: Bartonellosis, a globally emerging vector-borne zoonotic bacterial disease, is caused by hemotropic, gram-negative, aerobic, facultative intracellular Bartonella spp. (1). Of the 30 Bartonella species/subspecies, 17 have been associated with human infections (2,3). Each species has a reservoir host(s), within which the bacteria can cause intraerythrocytic bacteremia with few or no clinical signs of illness (1,3); the bacteria are transmitted by hematophagous arthropod vectors (1). Various Bartonella spp. have been identified in domestic and wild animals, including canids, deer, cattle, rodents, and marine mammals (1,4). Bartonella DNA from the blood of loggerhead sea turtles (Caretta caretta) has been PCR amplified and sequenced (5); the fact that Bartonella DNA was found suggests the possibility that persistent blood-borne infection can occur in nonmammals and that the host range for Bartonella spp. may be larger than anticipated. Growing evidence suggests that wild birds play key roles in the maintenance and movement of zoonotic pathogens such as tick-borne encephalitis virus and Borrelia and Rickettsia spp. (6–9). Bartonella grahamii DNA was amplified from a bird tick in Korea (10). The substantial mobility, broad distribution, and migrations of birds make them ideal reservoir hosts for dispersal of infectious agents. To investigate whether birds might be a reservoir for Bartonella spp., we screened 86 birds for the presence of Bartonella spp. DNA. The primary study site was a residential backyard in Morehead City, North Carolina, USA (34°43.722′N, 76°43.915′W). Of the 86 birds screened, 78 (16 species) were captured by mist net during March 2010–June 2012 and 8 (3 species) were injured birds that were to be euthanized (Table). Each bird was examined for external abnormalities and ectoparasites, weighed, measured, and tagged with a US Geological Survey–numbered band. A blood sample (0.10–0.25 mL) was collected from each bird by using a 1-mL insulin syringe with a 28-gauge × 1.27-cm needle. Blood remaining after preparation of blood smears was added to an EDTA tube and frozen (−80°C) until processed. Blood smears were examined for hemoparasites. Research was conducted under required state and federal bird banding permits and with the approval of the North Carolina State University Institutional Animal Care and Use Committee. Table Bartonella species detected in birds* Before DNA was extracted from the samples, 10 μL of blood was diluted in 190 µL of phosphate-buffered saline. DNA was automatically extracted by using a BioRobot Symphony Workstation and MagAttract DNA Blood M96 Kit (QIAGEN, Valencia, CA, USA). Bartonella DNA was amplified by using conventional Bartonella genus PCR primers targeting the 16S–23S intergenic spacer region: oligonucleotides, 425s (5′-CCG GGG AAG GTT TTC CGG TTT ATCC-3′) and 1,000as (5′-CTG AGC TAC GGC CCC TAA ATC AGG-3′). Amplification was performed in a 25-μL reaction, as described (3). All PCR reactions were analyzed by 2% agarose gel electrophoresis. Amplicons were sequenced to identify the Bartonella sp. and intergenic spacer region genotype. To compare sequences with those in GenBank, we identified bacterial species and genotypes by using Blast version 2.0 (http://blast.ncbi.nlm.nih.gov/Blast.cgi). DNA extraction and PCR-negative controls remained negative throughout the study. Results are summarized in the Table. None of the screened birds were anemic, but 5 were PCR positive for Bartonella spp. (3 for B. henselae and 2 for B. koehlerae). B. henselae was amplified from 2 Northern Mockingbirds (Mimus polyglottos) and 1 Red-winged Blackbird (Agelaius phoeniceus) (GenBank accession no. {"type":"entrez-nucleotide","attrs":{"text":"KC814161","term_id":"501412833","term_text":"KC814161"}}KC814161). The DNA sequences were identical to each other and had 99.6% (456/457 bp) sequence similarity with B. henselae San Antonio 2 intergenic spacer region genotype (GenBank accession no. {"type":"entrez-nucleotide","attrs":{"text":"AF369529","term_id":"15290601","term_text":"AF369529"}}AF369529). B. koehlerae was amplified from a Red-bellied Woodpecker (Melanerpes carolinus) and a Common Loon (Gavia immer) (GenBank accession no. {"type":"entrez-nucleotide","attrs":{"text":"KC814162","term_id":"501412834","term_text":"KC814162"}}KC814162). The DNA sequences were identical to each other (404/404 bp) and to GenBank sequence {"type":"entrez-nucleotide","attrs":{"text":"AF312490","term_id":"15277539","term_text":"AF312490"}}AF312490. Lice (Mallophaga order) were found on 5 Boat-tailed Grackles (Quiscalus major), but no ectoparasites were observed on Bartonella spp.–positive birds. Hemoparasites (Haemoproteus and Plasmodium spp.) were detected in 7 of 86 birds, indicating exposure to hematophagous ectoparasites, but hemoparasites were not detected in the Bartonella spp.–positive birds. No bacteria were visualized in Bartonella PCR–positive blood smears. Bartonella spp. are increasingly associated with animal and human illnesses; thus, the identification of reservoirs and increased understanding of Bartonella spp. disease ecology are of public health importance. Our finding of 2 pathogenic species not previously reported in birds has expanded the potential sources for zoonotic infection. There is growing evidence that migratory birds serve as reservoirs and/or mechanical vectors for pathogens such as tick-borne encephalitis virus and Rickettsia spp. (6–8). Birds have been implicated as reservoirs for several Borrelia spp. (9,10) and for possible dispersion of other tick-borne pathogens (e.g., Anaplasma and Bartonella spp.) (6,10). Tick transmission of Bartonella spp. to birds should be investigated, and additional studies that investigate the reservoir host range of Bartonella spp. and the transmission of these bacteria to non–host species will improve epidemiologic understanding of bartonellosis and will identify additional risk factors for Bartonella spp. transmission to new hosts, including humans.

Because of the relatively low biodiversity within arctic ecosystems, arctic foxes, Vulpes lagopus, could serve as sentinels for the study of changes in the ecology of vector-borne zoonotic pathogens. The objective of this study was to determine the molecular prevalence of 5 different genera of vector borne pathogens (Anaplasma, Babesia, Bartonella, Ehrlichia, and Hemotropic Mycoplasma spp.) using blood collected from 28 live-trapped arctic foxes from the region of Karrak Lake, Nunavut, Canada. Bartonella henselae (n = 3), Mycoplasma haemocanis (n = 1), Ehrlichia canis (n = 1), and an Anaplasma sp. (n = 1) DNA were PCR amplified and subsequently identified by sequencing. This study provides preliminary evidence that vector borne pathogens, not typically associated with the arctic ecosystem, exist at low levels in this arctic fox population, and that vector exposure, pathogen transmission dynamics, and changes in the geographic distribution of pathogens over time should be investigated in future studies.

A young woman experiencing depression, anxiety, mood swings, severe headaches, muscle spasms, interphalangeal joint stiffness, decreased peripheral vision, diminished tactile sensation, and hallucinations was persistently Bartonella koehlerae seroreactive and bacteremic. Following antibiotic treatment, B. koehlerae antibodies and DNA were not detected and all symptoms resolved.

Background Cats appear to be the primary reservoir host for Bartonella koehlerae, an alpha Proteobacteria that is most likely transmitted among cat populations by fleas (Ctenocephalides felis). Bartonella koehlerae has caused endocarditis in a dog and in one human patient from Israel, but other clinically relevant reports involving this bacterium are lacking. Despite publication of numerous, worldwide epidemiological studies designed to determine the prevalence of Bartonella spp. bacteremia in cats, B. koehlerae has never been isolated using conventional blood agar plates. To date, successful isolation of B. koehlerae from cats and from the one human endocarditis patient has consistently required the use of chocolate agar plates. Results In this study, Bartonella koehlerae bacteremia was documented in eight immunocompetent patients by PCR amplification and DNA sequencing, either prior to or after enrichment blood culture using Bartonella alpha Proteobacteria growth medium. Presenting symptoms most often included fatigue, insomnia, joint pain, headache, memory loss, and muscle pain. Four patients were also infected with Bartonella vinsonii subsp. berkhoffii genotype II. After molecular documentation of B. koehlerae infection in these patients, a serological test was developed and serum samples were tested retrospectively. Bartonella koehlerae antibodies were not detected (titers < 1:16) in 30 healthy human control sera, whereas five of eight patient samples had B. koehlerae antibody titers of 1:64 or greater. Conclusions Although biased by a study population consisting of individuals with extensive arthropod and animal exposure, the results of this study suggest that B. koehlerae bacteremia is more common in immunocompetent people than has been previously suspected. Future studies should more thoroughly define modes of transmission and risk factors for acquiring infection with B. koehlerae. In addition, studies are needed to determine if B. koehlerae is a cause or cofactor in the development of arthritis, peripheral neuropathies or tachyarrhythmias in patients.

Background In Argentina, only very few reports are available for canine tick-borne diseases where most are related to parasitic diseases. The objective of this survey was to investigate the prevalence of tick-borne pathogens in 70 dogs from Santa Fé and Córdoba, Argentina. Methods Microscopic blood smear examination as well as polymerase chain reaction (PCR) amplification using species-specific markers of Anaplasma, Babesia, Bartonella, Borrelia, Ehrlichia, Francisella, Mycoplasma (hemotropic group) and Rickettsia, followed by DNA sequencing were used to establish the prevalence of each infecting pathogen. Results Blood smear analysis showed 81% (57/70) prevalence of structures morphologically compatible with hemotropic mycoplasmas. No structures resembling either piroplasms or Anaplasma/Ehrlichia were detected. Hemotropic mycoplasma species (Mycoplasma haematoparvum, Mycoplasma haemocanis and Mycoplasma suis) were the most prevalent pathogens detected with an overall prevalence of 77.1%. Anaplasma platys was detected and identified in 11 of the 70 dogs (15.7%), meanwhile two Bartonella spp. (B. clarridgeiae and an uncharacterized Bartonella sp.) and Babesia vogeli were detected at 3 and 7% prevalence, respectively. Conclusions The work presented here describes a high molecular prevalence for hemotropic mycoplasma species in each of the five locations selected. Three Mycoplasma spp., including Mycoplasma suis, reported for the first time in dogs have been identified by DNA amplification and sequencing. This study highlights the risk that these bacterial pathogens represent for companion animals and, due to their potential zoonotic nature, also for people.

Background Bartonella species comprise a group of zoonotic pathogens that are usually acquired by vector transmission or by animal bites or scratches. Methods PCR targeting the Bartonella 16S-23S intergenic spacer (ITS) region was used in conjunction with BAPGM (Bartonella alpha Proteobacteria growth medium) enrichment blood culture to determine the infection status of the family members and to amplify DNA from spiders and woodlice. Antibody titers to B. vinsonii subsp. berkhoffii (Bvb) genotypes I-III, B. henselae (Bh) and B. koehlerae (Bk) were determined using an IFA test. Management of the medical problems reported by these patients was provided by their respective physicians. Results In this investigation, immediately prior to the onset of symptoms two children in a family experienced puncture-like skin lesions after exposure to and presumptive bites from woodlouse hunter spiders. Shortly thereafter, the mother and both children developed hive-like lesions. Over the ensuing months, the youngest son was diagnosed with Guillain-Barre (GBS) syndrome followed by Chronic Inflammatory Demyelinating Polyradiculoneuropathy (CIDP). The older son developed intermittent disorientation and irritability, and the mother experienced fatigue, headaches, joint pain and memory loss. When tested approximately three years after the woodlouse hunter spider infestation, all three family members were Bartonella henselae seroreactive and B. henselae DNA was amplified and sequenced from blood, serum or Bartonella alpha-proteobacteria (BAPGM) enrichment blood cultures from the mother and oldest son. Also, B. henselae DNA was PCR amplified and sequenced from a woodlouse and from woodlouse hunter spiders collected adjacent to the family’s home. Conclusions Although it was not possible to determine whether the family’s B. henselae infections were acquired by spider bites or whether the spiders and woodlice were merely accidental hosts, physicians should consider the possibility that B. henselae represents an antecedent infection for GBS, CIDP, and non-specific neurocognitive abnormalities.

Background During a two year period, a 27-year-old female veterinarian experienced migraine headaches, seizures, including status epilepticus, and other neurological and neurocognitive abnormalities. Prior to and during her illness, she had been actively involved in hospital-based work treating domestic animals, primarily cats and dogs, in Grenada and Ireland and anatomical research requiring the dissection of wild animals (including lions, giraffe, rabbits, mongoose, and other animals), mostly in South Africa. The woman reported contact with fleas, ticks, lice, biting flies, mosquitoes, spiders and mites and had also been scratched or bitten by dogs, cats, birds, horses, reptiles, rabbits and rodents. Prior diagnostic testing resulted in findings that were inconclusive or within normal reference ranges and no etiological diagnosis had been obtained to explain the patient’s symptoms. Methods PCR assays targeting Anaplasma spp. Bartonella spp. and hemotopic Mycoplasma spp. were used to test patient blood samples. PCR positive amplicons were sequenced directly and compared to GenBank sequences. In addition, Bartonella alpha Proteobacteria growth medium (BAPGM) enrichment blood culture was used to facilitate bacterial growth and Bartonella spp. serology was performed by indirect fluorescent antibody testing. Results Anaplasma platys, Bartonella henselae and Candidatus Mycoplasma haematoparvum DNA was amplified and sequenced from the woman’s blood, serum or blood culture samples. Her serum was variably seroreactive to several Bartonella sp. antigens. Despite symptomatic improvement, six months of doxycycline most likely failed to eliminate the B. henselae infection, whereas A. platys and Candidatus M. haematoparvum DNA was no longer amplified from post-treatment samples. Conclusions As is typical of many veterinary professionals, this individual had frequent exposure to arthropod vectors and near daily contact with persistently bacteremic reservoir hosts, including cats, the primary reservoir host for B. henselae, and dogs, the presumed primary reservoir host for A. platys and Candidatus Mycoplasma haematoparvum. Physicians caring for veterinarians should be aware of the occupational zoonotic risks associated with the daily activities of these animal health professionals.

Background Bartonella henselae is a zoonotic, alpha Proteobacterium, historically associated with cat scratch disease (CSD), but more recently associated with persistent bacteremia, fever of unknown origin, arthritic and neurological disorders, and bacillary angiomatosis, and peliosis hepatis in immunocompromised patients. A family from the Netherlands contacted our laboratory requesting to be included in a research study (NCSU-IRB#1960), designed to characterize Bartonella spp. bacteremia in people with extensive arthropod or animal exposure. All four family members had been exposed to tick bites in Zeeland, southwestern Netherlands. The mother and son were exhibiting symptoms including fatigue, headaches, memory loss, disorientation, peripheral neuropathic pain, striae (son only), and loss of coordination, whereas the father and daughter were healthy. Methods Each family member was tested for serological evidence of Bartonella exposure using B. vinsonii subsp. berkhoffii genotypes I-III, B. henselae and B. koehlerae indirect fluorescent antibody assays and for bacteremia using the BAPGM enrichment blood culture platform. Results The mother was seroreactive to multiple Bartonella spp. antigens and bacteremia was confirmed by PCR amplification of B. henselae DNA from blood, and from a BAPGM blood agar plate subculture isolate. The son was not seroreactive to any Bartonella sp. antigen, but B. henselae DNA was amplified from several blood and serum samples, from BAPGM enrichment blood culture, and from a cutaneous striae biopsy. The father and daughter were seronegative to all Bartonella spp. antigens, and negative for Bartonella DNA amplification. Conclusions Historically, persistent B. henselae bacteremia was not thought to occur in immunocompetent humans. To our knowledge, this study provides preliminary evidence supporting the possibility of persistent B. henselae bacteremia in immunocompetent persons from Europe. Cat or flea contact was considered an unlikely source of transmission and the mother, a physician, reported that clinical symptoms developed following tick exposure. To our knowledge, this is the first time that a B. henselae organism has been visualized in and amplified from a striae lesion. As the tick bites occurred three years prior to documentation of B. henselae bacteremia, the mode of transmission could not be determined.